CN1268482A - Method for prodn. of hydrogen chloride - Google Patents
Method for prodn. of hydrogen chloride Download PDFInfo
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- CN1268482A CN1268482A CN00105343A CN00105343A CN1268482A CN 1268482 A CN1268482 A CN 1268482A CN 00105343 A CN00105343 A CN 00105343A CN 00105343 A CN00105343 A CN 00105343A CN 1268482 A CN1268482 A CN 1268482A
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- hydrogen chloride
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/01—Chlorine; Hydrogen chloride
- C01B7/07—Purification ; Separation
- C01B7/0706—Purification ; Separation of hydrogen chloride
- C01B7/0712—Purification ; Separation of hydrogen chloride by distillation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/14—Fractional distillation or use of a fractionation or rectification column
- B01D3/143—Fractional distillation or use of a fractionation or rectification column by two or more of a fractionation, separation or rectification step
- B01D3/146—Multiple effect distillation
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Abstract
The process according to the invention comprises bringing gaseous hydrogen chloride in a non-condensable gas into contact with an absorbing medium selected from water or a dilute aqueous hydrogen chloride solution in an absorption column to cause the medium to absorb the gaseous hydrogen chloride, and subjecting the resultant absorbed solution to distillation in the presence of a salt having a salting-out effect to produce anhydrous hydrogen chloride.
Description
The present invention relates to a kind of method that contains aqueous hydrogen chloride solution production anhydrous hydrogen chloride by distillation.
As everyone knows, generation contains aqueous hydrogen chloride solution during certain density Azeotrope compositions is distilling under the distillation pressure.It is believed that, the temperature that is increased to azeotropic point when the atmospheric pressure from decompression when pressure increase and in the solution hydrogen cloride concentration in azeotropic point reduce.
People have found the liquid-gas equilibrium data of many hydrogenchloride-water binary system near azeotropic point under approaching atmospheric pressure in this case, for example by Sako, and T., Hakuta, T., Yoshitome, H., the J.Chem.Eng.Jpn. that is delivered, the 17th volume, 381 (1984 years).Yet it is found that liquid-gas equilibrium data seldom near azeotropic point.
In the middle of the document of the vapour-liquid equilibrium data of all disclosed high pressure system, Kao is arranged, J.T.F., J.Chem.Eng.Data, the 15th volume, 3,362 (1970) and Staple, B.G., Procopio Jr., J.M., Chem.Eng., November 16,113 (1970).
The highest hydrogen cloride concentration is 44.6% (weight) in last the disclosed data of document, and top temperature is 70 ℃, and the highest absolute pressure is 15 crust.The highest hydrogen cloride concentration is 35% (weight) in the disclosed data of document in back, and top temperature is 230 ℃, and the highest absolute pressure is 7MPa.
We propose on the basis of aforementioned each document now to reclaim and highly spissatedly contain aqueous hydrogen chloride solution and produce anhydrous hydrogen chloride by distillation many chemical processes from the rough hydrogenchloride that produces as by product or from the rough hydrogenchloride of the thermolysis gained of the waste liquid (from the vinyl chloride resin production process) by containing organic chloride.
Its example comprises the method in conjunction with vacuum distilling and pressure distillation that is disclosed in Japanese patent publication number 21318/1975, be disclosed in Japanese Patent openly the number of special permission 67504/1980 in conjunction with the adiabatic distillatory method that absorbs, be disclosed in Japanese Patent and openly specially permit No. 86901/1997 the method etc. that is used to produce anhydrous hydrogen chloride.
Above-mentioned chloride compound is burnt in calcining furnace, and pining for reclaiming the gained waste gas that contains hydrogenchloride and handle as about 350 ℃ gas (after this being called feed gas) at through exhaust gas boiler.
Fig. 5 is the schema of an embodiment of signal ordinary method.Adopt Fig. 5 explanation to be disclosed in method in the Japanese patent publication number 21318/1975.
In Fig. 5, contain the feed gas of hydrogenchloride and the bottom solution on absorption tower 1 offers expander 50 by pipeline 210 and 201 respectively with above-mentioned.In expander 50, contain hydrogenchloride in the feed gas of hydrogenchloride and be partially absorbed in the bottom solution on absorption tower 1, by pipeline 202 and 11 gained absorbent solution is sent to distillation tower 2.This moment, the absorbent solution by pipeline 202 contained iron ion etc., thereby regularly will partially absorb the solution taking-up by pipeline 203.
The feed gas that hydrogenchloride is therefrom partly shifted out imports in the absorption tower 1 by pipeline 8, and water or moisture hydrogenchloride diluent are then sent into by the pipeline 9 that is installed in 1 top, absorption tower.By filler, column plate or tower tray (not shown) liquids and gases are contacted to absorb remaining hydrogenchloride in tower.The crude aqueous hydrogen chloride solution that will be collected in 1 bottom, absorption tower by pipeline 201,202 and 11 is sent to distillation tower 2.Make remove the residue hydrogenchloride feed gas by pipeline 10 so that carry out individual curing.
To be sent to receptor 5 through pipeline 12 and condenser 4 from the distillation steam of cat head in distillation tower 2, phlegma refluxes through pipeline 13.The gaseous hydrogen chloride of normal atmosphere-0.2MPaG (pressure warning unit) is delivered to compressor 250 through pipeline 14, and being pressurized to 0.4-0.7MPaG therein becomes the pressurization anhydrous hydrogen chloride that uses separately as the feed material of other processes.
Method according to above-mentioned announcement is made up of an absorption tower and a distillation tower, thereby comparatively simple.But because the relation between the service temperature at the bottom of the working pressure of distillation tower and the tower, so working pressure must be limited in normal atmosphere-0.2MPaG so that make service temperature be no more than the temperature that the distillation tower material can bear.
As mentioned above, adopt anhydrous hydrogen chloride to need the working pressure of 0.4-0.7MPaG as the production method of the whole bag of tricks of feed material such as vinylchlorid.Therefore, need the pressure of feed material be brought up to its working pressure by compressor 250.Yet compressor 250 will suffer corrosion damage in this case.
Be disclosed in and be used in the Japanese patent application publication No. 86901/1997 produce method two distillation towers of employing of anhydrous hydrogen chloride and comprise: step 1, the aqueous hydrogen chloride solution feed material that contains that concentration is higher than the concentration of water and hydrogenchloride azeotropic point place under the working pressure is sent to first distillation tower, its distillation is contained aqueous hydrogen chloride solution and obtains highly spissated gaseous hydrogen chloride at cat head with the dilution that obtains Azeotrope compositions at the bottom of tower to the pressure of 0.2MPaG at normal atmosphere; Step 2, to be sent to second distillation tower by the aqueous hydrogen chloride solution that contains that the height condensed gaseous hydrogen chloride condensed that obtains is obtained in first distillation tower, at the pressure that surpasses 0.2MPaG be no more than under 160 ℃ the temperature its distillation, at the bottom of tower, obtain concentration just over the aqueous hydrogen chloride solution that contains corresponding to the Azeotrope compositions of above-mentioned pressure to obtain anhydrous hydrogen chloride at cat head; With step 3, will deliver in first distillation tower at the aqueous hydrogen chloride solution that contains that obtains at the bottom of second distillation Tata.The disclosure is pointed out the preferred material that adopts steel with fluoro-containing plastic lining etc. as first distillation tower, and the impervious graphite material is as the material of second distillation tower.But owing to use expensive impermeable graphite from the angle of industry is unpractical, so the document proposes not use this material.
As mentioned above, people attempt to develop a kind of method that is used to produce anhydrous hydrogen chloride, even it makes distillation tower bottom temperature can both remain under 0.4-0.7MPaG or the higher situation in the past in the operable temperature range of cheap material the operation of distillation tower being pressed do to bring up to.
Summary of the present invention
One of purpose of the present invention provides a kind of method that is used to produce anhydrous hydrogen chloride, even it can both remain in the past in the operable temperature range of cheap material distillation tower bottom temperature under the working pressure of distillation tower being brought up to 0.4MPa G or higher situation.
Even the inventor has done intensive research column bottom temperature still can be remained in the past in the operable temperature range of cheap material under the situation that improves distillation tower pressure.As a result, the salt that is selected from neutrality or basic alkaline earth metal muriate or alkali metal chloride when distillation under atmospheric pressure add wherein contain aqueous hydrogen chloride solution the time can be observed this salting-out effect: the bottom temp of distillation tower make us unexpectedly being significantly reduced the situation of salt (do not use when obtaining identical gaseous hydrogen chloride distillate relatively).We find further careful research, even still can observe identical salting-out effect under pressure.
Find that based on these we have finished the present invention, purpose of the present invention then is achieved by following manner.
A kind of method that is used to produce anhydrous hydrogen chloride, it comprises making and contains aqueous hydrogen chloride solution and distill, wherein distill the salt that in containing aqueous hydrogen chloride solution, has salting-out effect in the presence of carry out.
A kind of method that is used to produce anhydrous hydrogen chloride, it comprises makes the feed gas that comprises gaseous hydrogen chloride and a kind of not condensable gases be selected from the absorbing medium that water in the absorption tower or dilution contain aqueous hydrogen chloride solution and contact so that make absorbing medium absorb gaseous hydrogen chloride with at least a, and the absorbent solution of distillation gained is to produce anhydrous hydrogen chloride in distillation tower, and the absorbent solution that wherein is sent to distillation tower contains a kind of salt with salting-out effect.
A kind of method that is used to produce anhydrous hydrogen chloride, it comprises makes the feed gas that comprises gaseous hydrogen chloride and a kind of not condensable gases be selected from the absorbing medium that water in the absorption tower or dilution contain aqueous hydrogen chloride solution and contact so that make absorbing medium absorb gaseous hydrogen chloride with at least a, gained absorbent solution is sent in first distillation tower and the condenser above first distillation tower respectively, the absorbent solution that distillation is sent in first distillation tower, gas from first distillation tower cat head is contacted so that make condensation of gas with the absorbent solution of delivering to condenser, and distillation gained phlegma is to obtain anhydrous hydrogen chloride in second distillation tower, and the absorbent solution that wherein is sent to first distillation tower and condenser contains a kind of salt with salting-out effect.
Fig. 1 is the schema of signal one embodiment of the invention.
Fig. 2 is the schema of signal another embodiment of the invention.
Fig. 3 is the schema of another embodiment of signal the present invention.
Fig. 4 is the also schema of an embodiment of signal the present invention.
Fig. 5 is the schema of an embodiment of signal prior art.
In the present invention, at a kind of salt with salting-out effect, contain aqueous hydrogen chloride solution such as distillation under the existence of neutrality or basic alkaline earth metal chloride or alkali metal chloride. Can use the hydrogen chloride from various processes, can use in the present invention by making the various not condensable gases that contain hydrogen chloride and water or dilution contain that aqueous hydrogen chloride solution contacts in the absorption tower so that liquid absorption hydrogen chloride gained contain aqueous hydrogen chloride solution. Available water or contain aqueous hydrogen chloride solution and carry out quenching in order to it is sent in the absorption tower when the temperature of the not condensable gases that contains hydrogen chloride is higher.
To salt with salting-out effect add the position without limits, because of namely enough as long as this salt is present in the destilling tower bottom solution. Therefore this salt can add at place of any stage. For example, this salt can be joined water or the dilution of being sent to the absorption tower and contain in the aqueous hydrogen chloride solution, or join in the absorbent solution that is sent to destilling tower.
The concentration of salt with salting-out effect in containing aqueous hydrogen chloride solution of distilling is preferably 5-25% (weight), is particularly preferably 6-18% (weight).
The vapour pressure that hydrogen chloride is containing above the aqueous hydrogen chloride solution in the presence of above-mentioned salt is improved. This phenomenon so that the distillation pressure of moisture hydrogen chloride be increased and need not improve operating temperature. Even therefore adopt the various cheap polymeric material that has used so far also can increase the operating pressure of destilling tower. Kind and quantity by salt contained in the suitable selection solution can control salting-out effect.
When the salt with salting-out effect was present in to absorb the absorbing medium of hydrogen chloride from the feed gas that contains hydrogen chloride, this salt may produce an adverse effect to absorbing operation. But it is little of negligible degree to the impact of absorption tower operating temperature range.
Carrying out according to the present invention in the production of anhydrous hydrogen chloride, the aqueous hydrogen chloride solution that contains of hydrogen cloride concentration that makes under the pressure of destilling tower its hydrogen cloride concentration be higher than the azeotropic point place of hydrogen chloride and water distills.
The distillation that contains aqueous hydrogen chloride solution can be carried out in one or two stage, and it comprises that pressure is preferably the first time distillation of 0.05-0.2MPaG and pressure and is preferably and is not less than 0.4 MPaG and column bottom temperature is no more than 150 ℃ the distillation second time.
It is following that the present invention will be described with reference to each accompanying drawing.The numeral and the symbol that use among Fig. 1-5 are consistent.
Fig. 1 is the schema of signal one embodiment of the invention.In Fig. 1, contain the feed gas of hydrogenchloride and the bottom solution on absorption tower 1 and be sent to expander 50 through pipeline 210 and 201 respectively.In expander 50, the part hydrogenchloride that contains the feed gas of hydrogenchloride is absorbed in the bottom solution on absorption tower 1.Gained absorbent solution by pipeline 202 and 11 is converged with salt 7 through pipeline 19 chargings and is sent to distillation tower 2 with the form of dissolved salt 7.The hydrogen cloride concentration of absorbent solution is higher than the hydrogen cloride concentration that is in hydrogenchloride and water azeotropic point place under the distillation tower pressure.Therefore will partially absorb solution and termly through pipeline 203 discharge (as prior art method as carry out) because above-mentioned absorbent solution contains iron ion etc. this moment.
With hydrogenchloride therefrom the feed gas removed of part import in the absorption tower 1 through pipeline 8, send into to absorb remaining hydrogenchloride through the pipeline 9 that is placed in 1 top, absorption tower and water or dilution are contained aqueous hydrogen chloride solution.To discharge so that carry out individual curing through pipeline 10 except that the feed gas of de-chlorine hydride.
To absorb liquid and mix from the solution of following distillation tower 2 bottoms through pipeline 17, water cooler 6 and pipeline 18 chargings this moment, form the crude aqueous hydrogen chloride solution that is collected in 1 bottom, absorption tower.This crude aqueous hydrogen chloride solution that contains the salt with salting-out effect 1 bottom is sent to expander 50 with absorbing hydrogen chloride through pipeline 201 from the absorption tower.As above-mentioned absorbent solution with gained termly through discharging (blown) from pipeline 202 ramose pipelines 203.The salt 7 corresponding with the salt of discharging through 203 pipelines such as grade provides by pipeline 19.Situation in following Fig. 3 also is like this.
Salt with salting-out effect can preferably include neutrality or basic alkaline earth metal muriate or alkali metal chloride.Alkaline earth metal chloride is better than alkali metal chloride, and cheap Ca, Mg and Ba can be used as alkaline-earth metal.Beyond all doubt these metals can use separately, and form that also can mixture is used.
Situation in following Fig. 2-4 also is like this.
The concentration of salt with salting-out effect is different with the difference of the solubleness of this salt in containing aqueous hydrogen chloride solution, but can select to make that being lower than this salt under service temperature is dissolved in the solubleness that contains aqueous hydrogen chloride solution and should have solid precipitation under this concentration when with this solution cooling.In other words, this concentration should be lower than in the operation system at this salt under the minimum temperature of system and containing solubleness in the aqueous hydrogen chloride solution.Specifically, can preferably adopt above-mentioned concentration range.
Situation in following Fig. 2-4 also is like this.
To be forced into 0.4-07MPaG by the saliferous crude aqueous hydrogen chloride solution that pipeline 11 is carried and be sent to distillation tower 2 by the pump (not shown) with 60-80 ℃ temperature, wherein, be that 0.4-07MPaG and bottom temp are about under 142-143 ℃ the condition and distill by reboiler 3 heating that are placed in the distillation tower bottom at pressure.So obtain the gaseous state anhydrous hydrogen chloride of 0.4-07MPaG from the top of tower 2 by pipeline 12, condenser 4, receptor 5 and pipeline 14.
On the other hand, the aqueous hydrogen chloride solution that contains that makes temperature from the bottom be about 142-143 ℃ is carried by pipeline 15 and 17, is cooled to about 35-50 ℃ in water cooler 6, and enters in the absorption tower 1 through pipeline 18.
The working pressure of distillation tower 1 is selected the pressure of 0.4-07MPaG usually for use.But working pressure is not limited to this pressure range.Need not say, can select to be not less than the pressure of 0.7MPaG such as 0.7-1.5MPaG.
Fig. 2 is the schema of signal another embodiment of the invention.In the method for Fig. 1, when taking-up partially absorbs solution, also take out the salt of part so that from solution, remove iron ion etc., and in the method for Fig. 2, when removing, salt is not taken out.It is following that the present invention will be described with reference to Fig. 2.
In Fig. 2, will contain hydrogenchloride, be sent in the expander 50 through pipeline 210, pipeline 202 and 204, water cooler 60 and pipeline 205 and by pipeline 207 respectively from the chilling solution of expander 50 and the feed gas of moisture.If the amount of the water by pipeline 207 chargings can alleviate the load of following water cooler 60 then be enough.
The chilling solution through pipeline 202 and 204 conveyings that temperature is generally 60-80 ℃ are sent into water cooler 60, wherein are cooled to 35-70 ℃.Solution mixes by pipeline 205 and with water from pipeline 207 and makes it be circulated to expander 50 by pipeline 206 then.
All adopt similarly termly part chilling solution through removing, because of it contains iron ion etc. for prior art from pipeline 202 ramose pipelines 203.In Fig. 2, salt 7 according to the present invention is not present in the solution that pipeline 203 is removed.Situation in following Fig. 4 also is like this.
The feed gas that hydrogenchloride part is taken out imports in the absorption tower 1 through pipeline 8, water or dilution contain aqueous hydrogen chloride solution then pipeline 9 chargings through being placed in 1 top, absorption tower to absorb remaining hydrogenchloride, on the other hand, the feed gas of having removed hydrogenchloride is discharged so that handle separately by pipeline 10.
With gained absorbent solution with mix the crude aqueous hydrogen chloride solution that is collected in 1 bottom, absorption tower with formation through pipeline 17, water cooler 6 and pipeline 18 from following distillation tower 2 underfeed solution.The absorbent solution of the salt of sending into through pipeline 19 in the time of will containing from the operation beginning with salting-out effect 7 is sent to the distillation tower 2 through the bottom of pipeline 11 from absorption tower 1.Need not illustrate, needn't provide salt 7 usually during operation.Situation in following Fig. 4 also is like this.
To be forced into 0.4-07MPaG by the saliferous absorbent solution that pipeline 11 is carried and be sent to distillation tower 2 by the pump (not shown) with 70-80 ℃ temperature, wherein, be preferably under the condition that 0.4-07MPaG and bottom temp preferably be about 142-143 ℃ at pressure and distill by reboiler 3 heating that are placed in distillation tower 2 bottoms.So obtain the gaseous state anhydrous hydrogen chloride of 0.4-07MPaG from the top of tower 2 by pipeline 12, condenser 4, receptor 5 and pipeline 14.
On the other hand, 142-143 ℃ the aqueous hydrogen chloride solution that contains of being about that will discharge from tower 2 bottoms is transported to water cooler 6 by pipeline 15 and 17, is cooled to about 35-50 ℃ therein, and enters in the absorption tower 1 through pipeline 18.
Fig. 3 is the schema of another embodiment of signal the present invention.The present invention is described with reference to Fig. 3 and Fig. 1.
In Fig. 3, will contain the feed gas of hydrogenchloride and be sent to expander 50 by pipeline 210 and 201 respectively from the absorbent solution on absorption tower 1.In expander 50, the part hydrogenchloride that contains in the feed gas of hydrogenchloride is absorbed in the bottom solution on absorption tower 1.The gained absorbent solutions of carrying through pipeline 202 and 11 are mixed with the salt 7 through pipeline 19 chargings, make this salt 7 offer distillation tower 20 with the dissolved state.Simultaneously, because the absorbent solution through pipeline 202 contains iron ion etc., therefore regularly will partially absorb solution removal by ramose pipeline 203 from pipeline 202, salt 7 then provides (carrying out as the method that is set forth among Fig. 1) with the salt amount of removing through pipeline 203 corresponding to salt by pipeline 19.
On the other hand, the feed gas that hydrogenchloride part is therefrom taken out imports in the absorption tower 1 through pipeline 8, water or dilution contain aqueous hydrogen chloride solution then pipeline 9 chargings through being placed in 1 top, absorption tower to absorb remaining hydrogenchloride.Having removed the feed gas of hydrogenchloride discharges so that handle (carrying out as the method that is set forth among Fig. 1) separately by pipeline 10.
Then by pipeline 115,, pipeline 123, water cooler 6 and pipeline 18 deliver to absorption tower 1 with the bottom solution of first distillation tower 20, therein with contain aqueous hydrogen chloride solution through the water of pipeline 9 chargings or dilution and converge to absorb remaining gaseous hydrogen chloride, obtain being collected in the absorbent solution (crude aqueous hydrogen chloride solution) of 1 bottom, absorption tower.
Saliferous crude aqueous hydrogen chloride solution that will be through operating under the temperature normal atmosphere and 60-80 ℃ that pipeline 11 is carried is sent to first distillation tower 20 and through be sent to the condenser 40 that is placed in above first distillation tower 20 from pipeline 11 ramose pipelines 111 through pipeline 110 respectively.Therein, at the pressure of 0.05-0.2MPaG and be about under 125-143 ℃ the condition of column bottom temperature, will deliver to the solution distillation of first distillation tower 20 by in the reboiler 30 that is placed in first distillation tower, 20 bottoms, heating.Will be in condenser 40 by contacting from the height condensed gaseous hydrogen chloride condensed at first distillation tower, 20 tops with the saliferous crude aqueous hydrogen chloride solution of delivering to condenser 40, obtain phlegma, contain aqueous hydrogen chloride solution through pipeline 113, pump 25 and pipeline 114 as highly spissated saliferous then and be sent to second column 200.
On the other hand, will be about 125-143 ℃ dilution from the temperature of first distillation tower, 20 bottoms and contain aqueous hydrogen chloride solution and be sent to water cooler 6, and be cooled to about 35-50 ℃ therein, and be circulated in the absorption tower 1 through pipeline 18 by pipeline 115 and 123.
The concentrated aqueous hydrogen chloride solution of saliferous height of delivering to second column 200 0.4-1.5MPaG, the pressure that is preferably 0.7-1.0MPaG and 130-150 ℃, be preferably 135-145 ℃, more preferably distill in tower 200 by reboiler 300 heating under 140-143 ℃ the temperature in distillation tower 200 bottoms.Solution turns back in first distillation tower 20 through 120 and 122 at the bottom of the tower.Obtain the gaseous state anhydrous hydrogen chloride of 0.4-1.5MPaG respectively by pipeline 117, condenser 4, receptor 5 and pipeline 119.
Fig. 4 is the also schema of an embodiment of signal the present invention.Salt takes out with the absorbent solution of removing in Fig. 3, and salt does not take out with absorbent solution in Fig. 4.The present invention describes referring now to following Fig. 4 and Fig. 2.
In Fig. 4, respectively by pipeline 210, pipeline 202, pipeline 204, water cooler 60 and pipeline 205 and by pipeline 207 will contain hydrogenchloride feed gas, be sent in the expander 50 from the expander solution and the water of expander 50.If can reduce the load of following water cooler 60 then enough (as the situation of Fig. 2 method) through the amount of the water of pipeline 207 chargings.
Expander solution is sent into water cooler 60 through pipeline 202 and 204 usually under 60-80 ℃, be cooled to 35-70 ℃ therein.So cooled solution is sent through pipeline 205, converges with water through pipeline 207 and delivers to again in the expander 50 by pipeline 206.
Because the solution the pipeline 203 that comes out from pipeline 202 branches contains iron ion etc., therefore termly this solution of part is removed through pipeline 203 as the same way as in Fig. 2 method.Be similar to method shown in Fig. 2, the solution by pipeline 203 in Fig. 4 does not contain according to salt 7 of the present invention.
Respectively the hydrogenchloride feed gas removed of part is sent into absorption tower 1 and water or dilution are contained aqueous hydrogen chloride solution through pipeline 8 and send into to absorb remaining hydrogenchloride through the pipeline 9 that is placed in 1 top, absorption tower.Having removed the feed gas of hydrogenchloride discharges so that handle separately by pipeline 10.
To send into absorption tower 1 through pipeline 115, pipeline 123, water cooler 6 and pipeline 18 from the solution of first distillation tower, 20 bottoms, therein with contain aqueous hydrogen chloride solution through the water of pipeline 9 chargings or dilution and converge to absorb remaining gaseous hydrogen chloride, obtain being collected in the crude aqueous hydrogen chloride solution of 1 bottom, absorption tower.
The saliferous absorbent solution (crude aqueous hydrogen chloride solution) that to operate under the temperature normal atmosphere and 70-80 ℃ that pipeline 11 is carried is sent to first distillation tower 20 and through being sent to the condenser 40 that is placed in first distillation tower, 20 tops from pipeline 11 ramose pipelines 111 through pipeline 110 respectively.Therein, at the pressure of 0.05-0.2MPaG and be about under 125-143 ℃ the condition of column bottom temperature, will deliver to the absorbent solution distillation of first distillation tower 20 by in the reboiler 30 that is placed in first distillation tower, 20 bottoms, heating.Will be in condenser 40 by contacting from the height condensed gaseous hydrogen chloride condensed at first distillation tower, 20 tops with the saliferous absorbent solution of delivering to condenser 40, obtain phlegma, will be sent to second column 200 for the concentrated aqueous hydrogen chloride solution of saliferous height through pipeline 113, pump 25 and pipeline 114 then.
To be about 125-143 ℃ dilution from the temperature of first distillation tower, 20 bottoms and contain aqueous hydrogen chloride solution and deliver to water cooler 6, be cooled to 35-50 ℃ therein, turn back in the absorption tower 1 through pipeline 18 then through pipeline 115 and 123.
The concentrated aqueous hydrogen chloride solution of saliferous height of delivering to second column 200 0.4-1.5MPaG, the pressure that is preferably 0.7-1.0MPaG and 130-150 ℃, be preferably 135-145 ℃, more preferably under 140-143 ℃ the temperature by in reboiler 300 heating of distillation tower 200 bottoms and in tower 200, distill.Solution is recycled in first distillation tower 20 through pipeline 120 and 122 at the bottom of the tower, and obtains the gaseous state anhydrous hydrogen chloride of 0.4-1.5MPaG by pipeline 117, condenser 4, receptor 5 and pipeline 119.
The present invention is concrete to be described with reference to following each embodiment.Need not illustrate that the present invention only is confined to these embodiment.
One operation is carried out according to Fig. 1 method.The feed gas (obtaining by the waste liquid that contains chlorinated organic cpd in the burning chemical plant) that will contain hydrogenchloride is sent into absorption tower 1 through pipeline 8, and water is then sent into absorbing hydrogen chloride through the pipeline 9 that is placed in 1 top, absorption tower.The hydrogenchloride that consists of concentration 25% (weight) of the crude aqueous hydrogen chloride solution by pipeline 11, its feeding rate is 18.2 tons/hour.This crude aqueous hydrogen chloride solution contains 17% (weight) as the CaCl with salt of salting-out effect
2The crude aqueous hydrogen chloride solution is delivered to distillation tower 2 through pipeline 11 under 70 ℃ temperature, wherein distill heating in by the reboiler 3 that is being placed in distillation tower 2 bottoms under the column bottom temperature of the pressure of 0.5MPaG and 143 ℃.Obtain the gaseous state anhydrous hydrogen chloride of 0.5MPaG through pipeline 12, condenser 4, receptor 5 and pipeline 14 from the top of tower 2.
Hydrogen cloride concentration is that the aqueous hydrogen chloride solution that contains of 25% (weight) is sent to water cooler 6 (being cooled to 50 ℃ therein) and is sent to absorption tower 1 through pipeline 18 through pipeline 15 and 17 respectively in tower 2 bottoms.
With the various operational conditions of aforesaid method with the results are shown in the table 1.
Table 1
Symbol | Embodiment 1 | Embodiment 2 | Embodiment 3 | Embodiment 4 | Comparing embodiment 1 | Comparing embodiment 2 | Embodiment 5 | Embodiment 6 |
Kind absorption tower 1 pressure of salt, (MPaG) destilling tower 2 pressure, (MPaG) column bottom temperature, (℃) destilling tower 20 pressure, (MPaG) column bottom temperature, (℃) destilling tower 200 pressure, (MPaG) column bottom temperature, (℃) pipeline 210, (feed gas) flow velocity, (ton/hour) temperature, (℃) pipeline 11 flow velocitys, (ton/hour) HCl concentration, (salt-free), (% by weight) pressure, (MPaG) temperature, (℃) salinity, (% by weight) | ??CaCl 2??0.01 ??0.50 ??143 ???- ???- ???- ???-? ? ??16.0 ??350 ??18.2 ??25 ??0.01 ??70 ??17 | ????MgCl 2????0.01 ????0.50 ????143 ?????- ?????- ?????- ?????-? ? ????16.0 ????350 ????17.6 ????25 ????0.01 ????70 ????14 | ????CaCl 2????0.01 ?????- ?????- ????0.15 ????133 ????1.0 ????143? ? ????16.0 ????350 ????21.4 ????24 ????0.01 ????70 ????8.5 | ????MgCl 2????0.01 ?????- ?????- ????0.15 ????133 ????1.0 ????143? ? ????16.0 ????350 ????21 ????24 ????0.01 ????70 ????6.7 | ?????- ????0.01 ????0.23 ????143 ?????- ?????- ?????- ?????-? ? ????16.0 ????350 ????15.1 ????25 ????0.01 ????70 ????0 | ????- ????0.01 ????0.50 ????165 ????- ????- ????- ????-? ? ????16.0 ????350 ????15.1 ????25 ????0.01 ????70 ????0 | ????CaCl 2????0.01 ????0.50 ????143 ?????- ?????- ?????- ?????-? ? ????16.0 ????350 ????18.2 ????25 ????0.01 ????61 ????17 | ??CaCl 2??0.01 ???- ???- ??0.15 ??133 ??0.15 ??143? ? ??16.0 ??350 ??21.4 ??24 ??0.01 ??61 ??8.5 |
Table 1 (continuous table)
| Embodiment | 1 | | | Embodiment 4 | Comparing | Comparing | | |
| ? ????1.0 ????100? ? ????17.1 ????20 ????0.50 ????50 ????18? ? ????-? ? ????-? ? ????- ????-? ? ????- ????- ????- | ? ????1.0 ????100? ? ????16.5 ????20 ????0.50 ????50 ????15? ? ????-? ? ????-? ? ????- ????-? ? ????- ????- ????- | ? ?????- ?????-? ? ????20.2 ????20 ????0.15 ????50 ????9.1? ? ????8.9? ? ????12.5? ? ????17.5 ????34.3? ? ????0.14 ????65 ????6.1 | ? ????- ????-? ? ????19.8 ????20 ????0.15 ????50 ????7.3? ? ????8.7? ? ????12.3? ? ????17.3 ????34.3? ? ????0.14 ????65 ????4.9 | ? ????1.0 ????100? ? ????14 ????20 ????0.23 ????50 ????0? ? ?????-? ? ?????-? ? ?????- ?????-? ? ?????- ?????- ?????- | ? ????1.0 ????100? ? ????14 ????20 ????0.50 ????50 ????0? ? ????-? ? ????-? ? ????- ????-? ? ????- ????- ????- | ? ????1.0 ????100? ? ????17.1 ????20 ????0.50 ????50 ????1.8? ? ????-? ? ????-? ? ????- ????-? ? ????- ????- ????- | ? ?????- ?????-? ? ????20.2 ????20 ????0.15 ????50 ????9.1? ? ????8.9? ? ????12.5? ? ????17.5 ????34.3? ? ????0.14 ????65 ????6.1 |
Table 1 (continuous table)
| Embodiment | 1 | | | Embodiment 4 | Comparing | Comparing | | |
| ? ????- ????-? ? ????- ????- ????- ????- ????-? ? ????0.23? ? ????65? ? ????- | ? ????- ????-? ? ????- ????- ????- ????- ????-? ? ????0.18? ? ????65? ? ????- | ? ????1.0 ????100? ? ????16.5 ????30 ????1.0 ????143 ????6.5? ? ????0.14? ? ????65? ? ????- | ? ????1.0 ????100? ? ????16.3 ????30 ????1.0 ????143 ????5.2? ? ????0.08? ? ????65? ? ????- | ? ????- ????-? ? ????- ????- ????- ????- ????-? ? ????-? ? ????65? ? ????- | ? ????- ????-? ? ????- ????- ????- ????- ????-? ? ????-? ? ????65? ? ????- | ? ????- ????-? ? ????- ????- ????- ????- ????-? ? ????0? ? ????65? ? ????0.4 | ? ????1.0 ????100? ? ????16.5 ????30 ????1.0 ????143 ????6.5? ? ????0? ? ????60? ? ????0.4 |
HCl concentration (salt-free) (weight %)=(quality of HCl in the solution)/[(quality of HCl in the solution)+(quality of water in the solution)] * 100
To operate with embodiment 1 identical mode, difference is 17% among the embodiment 1 (weight) CaCl
2Be 14% (weight) MgCl
2Substitute.
Its various operational conditions and result also are shown in Table 1.
Comparing embodiment 1
To carry out an operation with embodiment 1 identical mode, difference is CaCl among the embodiment 1
2Concentration be changed to 0% (weight) from 17% (weight), pressure is changed to 0.23MPaG from 0.5MPaG.Its various operational conditions and result also are shown in Table 1.
Comparing embodiment 2
To carry out an operation with embodiment 1 identical mode, difference is CaCl among the embodiment 1
2Concentration be changed to 0% (weight).Its various operational conditions and result also are shown in Table 1.
Method according to Fig. 3 is operated.To send in the absorption tower 1 through pipeline 8 by the feed gas that contains hydrogenchloride that waste liquid produced that chlorinated organic cpd is contained in the burning chemical plant, the water then pipeline through being placed in top, absorption tower 9 sprays into absorbing hydrogen chloride.Hydrogenchloride is 24% (weight) in the composition of the crude aqueous hydrogen chloride solution by pipeline 11, and its feeding rate is 21.4 tons/hour.The crude aqueous hydrogen chloride solution contains 8.5% (weight) as the CaCl with salt of salting-out effect
2
Enter the condenser 40 that is placed in above first distillation tower 20 entering distillation tower 20 and pipeline 111 through pipeline 110 respectively through the saliferous crude aqueous hydrogen chloride solution of pipeline 11 chargings under 70 ℃ through coming out from pipeline 11 branches.Its flow velocity is respectively 8.9 tons/hour and 12.5 tons/hour.The solution that is sent to first distillation tower 20 under the column bottom temperature of the pressure of 0.15MPaG and 143 ℃ distills therein.Will be in condenser 40 from the height condensed gaseous hydrogen chloride condensed at the first distillation tower top, obtain phlegma, converge with the saliferous absorbent solution of delivering to condenser 40 again and be sent in the second column 200 through pipeline 113, pump 25 and pipeline 114 as the spissated aqueous hydrogen chloride solution that contains of saliferous height.
On the other hand, will contain aqueous hydrogen chloride solution from 143 ℃ dilution of first distillation tower, 20 bottoms and deliver to water cooler 6, be cooled to 50 ℃ therein, turn back in the absorption tower 1 through pipeline 18 again through pipeline 115 and 123.
The concentrated aqueous hydrogen chloride solution of saliferous height that will be sent to second column 200 under the column bottom temperature of the pressure of 1.0MPaG and 143 ℃ distills therein.Bottom solution turns back in first distillation tower 20 through pipeline 120 and 122, and obtains the gaseous state anhydrous hydrogen chloride of 1.0MPaG by pipeline 117, condenser 4, receptor 5 and pipeline 119.
Various operational conditions and result also are shown in Table 1.
Embodiment 4
Adopt MgCl
2Replace the CaCl among the embodiment 3
2Operate.
Various operational conditions and operating result also are shown in Table 1.
Method according to Fig. 2 is operated.
Various operational conditions and operating result also are shown in Table 1.
Method according to Fig. 4 is operated.
Various operational conditions and operating result also are shown in Table 1.
Method according to the present invention for the production of anhydrous hydrogen chloride can obtain following result.
(1) owing to there is the salt with salting-out effect, thereby destilling tower can and even be not less than under the pressure of 0.4MPaG and operating in the temperature about 140 ℃. Therefore use aforementioned cheap material as the material of the destilling tower possibility that becomes.
(2) since the distillation step can in a destilling tower, operate being not less than under the pressure of 0.4MPaG, thereby save in the prior art the compressor that is used for making anhydrous hydrogen chloride be forced into this pressure possibility that becomes, so that can omit compression step to reduce compression energy, the etching problem relevant with compressor also can be solved fully simultaneously.
(3) though adopt two destilling towers so that under the pressure that is higher than 0.4MPaG far away (this is the operating pressure that in the past used) also can distill step. Therefore, need not adopt compressor the pressure of anhydrous hydrogen chloride can be adjusted to the pressure condition that anhydrous hydrogen chloride is used as the method for feed material therein.
(4) the method also can operate in the situation that need not remove the salt with salting-out effect.
Claims (13)
1. method that is used to produce anhydrous hydrogen chloride, it comprises making and contains aqueous hydrogen chloride solution and distill, wherein said distillation described contain salt in the aqueous hydrogen chloride solution with salting-out effect in the presence of carry out.
2. method that is used to produce anhydrous hydrogen chloride, it comprises makes the feed gas that comprises gaseous hydrogen chloride and uncondensable gas be selected from the absorbing medium that water or dilution contain aqueous hydrogen chloride solution and contact in the absorption tower so that absorbing medium absorbs described gaseous hydrogen chloride with at least a, and the absorbent solution of distilling gained in distillation tower wherein is sent to the interior absorbent solution of described distillation tower and contains the salt with salting-out effect to produce anhydrous hydrogen chloride.
3. according to the method for claim 2, wherein adopt water or dilution to contain aqueous hydrogen chloride solution the described feed gas of pyritous is carried out chilling, in the absorption tower, contact then with described absorbing medium.
4. according to the method for claim 2, wherein said dilution contains the bottom solution that aqueous hydrogen chloride solution is described distillation tower.
5. according to the method for claim 3, the dilution that wherein is used for described chilling contains aqueous hydrogen chloride solution and is the absorbent solution from described absorption tower, and the absorbent solution that is used for the described feed gas of chilling is distilled at described distillation tower.
6. method that is used to produce anhydrous hydrogen chloride, it comprises makes the feed gas that comprises gaseous hydrogen chloride and uncondensable gas be selected from the absorbing medium that water or dilution contain aqueous hydrogen chloride solution and contact in the absorption tower so that make described absorbing medium absorb described gaseous hydrogen chloride with at least a, gained absorbent solution is delivered to first distillation tower respectively and is placed in the condenser on the first distillation tower top, absorbent solution is wherein sent in distillation in first distillation tower, in described condenser, make from the gas of the first distillation tower cat head and contact so that described condensation of gas with absorbent solution in sending into described condenser, the gained phlegma is distilled in second column to produce anhydrous hydrogen chloride, and the absorbent solution of wherein delivering in described first distillation tower and the described condenser contains the salt with salting-out effect.
7. according to the method for claim 6, the pressure of wherein said first distillation tower is 0.05-0.2MPaG.
8. according to the method for claim 6, the pressure of wherein said second column is not less than 0.4MPaG and column bottom temperature is no more than 150 ℃.
9. according to the method for claim 6, wherein adopt water or dilution to contain aqueous hydrogen chloride solution the described feed gas of pyritous is carried out chilling, in the absorption tower, contact then with described absorbing medium.
10. according to the method for claim 6, it is from solution at the bottom of the tower of described first distillation tower bottom that wherein said dilution contains aqueous hydrogen chloride solution, and has the composition near water and hydrogenchloride Azeotrope compositions.
11. according to the method for claim 6, solution is sent to the top of described first distillation tower so that distill at the bottom of the tower of wherein said second column.
12. according to claim 1,2 or 6 method, wherein said salt with salting-out effect is at least a salt that is selected from neutral and basic alkaline earth metal muriate and alkali metal chloride.
13. according to claim 1,2 or 6 method, the described salt that wherein has salting-out effect is 5-25% (weight) in the described concentration that contains in the aqueous hydrogen chloride solution.
Applications Claiming Priority (6)
Application Number | Priority Date | Filing Date | Title |
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JP9200599 | 1999-03-31 | ||
JP92005/1999 | 1999-03-31 | ||
JP30232499 | 1999-10-25 | ||
JP302324/1999 | 1999-10-25 | ||
JP11554/2000 | 2000-01-20 | ||
JP2000011554A JP2001192202A (en) | 1999-03-31 | 2000-01-20 | Process for manufacturing anhydrous hydrogen chloride |
Publications (1)
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CN1268482A true CN1268482A (en) | 2000-10-04 |
Family
ID=27306896
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CN00105343A Pending CN1268482A (en) | 1999-03-31 | 2000-03-31 | Method for prodn. of hydrogen chloride |
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US (1) | US6540973B1 (en) |
JP (1) | JP2001192202A (en) |
CN (1) | CN1268482A (en) |
Cited By (3)
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CN102502500A (en) * | 2011-11-07 | 2012-06-20 | 韩扶军 | Device for producing hydrogen chloride by resolving hydrochloric acid |
CN102826512A (en) * | 2011-06-16 | 2012-12-19 | 跨特株式会社 | Manufacturing method and apparatus of high-purity hydrogen chloride |
CN107848799A (en) * | 2015-08-10 | 2018-03-27 | 昭和电工株式会社 | Chlorination method for preparing hydrogen |
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EP1636829B1 (en) * | 2003-06-12 | 2016-11-23 | Georgia Tech Research Corporation | Patterned thin film graphite devices |
JP5374783B2 (en) * | 2008-12-03 | 2013-12-25 | 住友化学株式会社 | Purification method of hydrochloric acid |
US8497499B2 (en) * | 2009-10-12 | 2013-07-30 | Georgia Tech Research Corporation | Method to modify the conductivity of graphene |
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JP5946740B2 (en) * | 2012-10-04 | 2016-07-06 | 住友精化株式会社 | Anhydrous hydrogen chloride purification method and anhydrous hydrogen chloride purification apparatus |
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CN109437108A (en) * | 2018-11-22 | 2019-03-08 | 衡阳恒荣高纯半导体材料有限公司 | A kind of waste acidity recovery 26%-28% hydrogen chloride new process |
JP2023535427A (en) * | 2020-07-22 | 2023-08-17 | エスジーエル・カーボン・エスイー | High pressure desorption of hydrogen chloride gas |
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NO123796B (en) * | 1970-07-17 | 1972-01-17 | Norsk Hydro As | |
JPS5021318A (en) | 1973-06-28 | 1975-03-06 | ||
DE2633640C3 (en) * | 1976-07-27 | 1979-03-15 | Chemische Werke Huels Ag, 4370 Marl | Process for the production of gaseous hydrogen chloride from dilute aqueous hydrochloric acid |
JPS5567504A (en) | 1978-11-16 | 1980-05-21 | Nittetsu Kakoki Kk | Production of high concentration hydrochloric acid |
US4259309A (en) * | 1979-08-08 | 1981-03-31 | Chemische Werke Huls Ag | Method for obtaining gaseous hydrogen chloride from dilute aqueous hydrochloric acid |
US4867960A (en) * | 1987-01-29 | 1989-09-19 | Hercules Incorporated | Water scavengers for hydrochloric acid streams |
DE3816783A1 (en) * | 1988-05-17 | 1989-11-30 | Wacker Chemie Gmbh | METHOD FOR PURIFYING RAW, GASEOUS CHLORINE |
JP3558101B2 (en) | 1995-09-26 | 2004-08-25 | 日鉄化工機株式会社 | Manufacturing method of anhydrous hydrochloric acid |
-
2000
- 2000-01-20 JP JP2000011554A patent/JP2001192202A/en not_active Withdrawn
- 2000-02-28 US US09/513,944 patent/US6540973B1/en not_active Expired - Fee Related
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
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CN102826512A (en) * | 2011-06-16 | 2012-12-19 | 跨特株式会社 | Manufacturing method and apparatus of high-purity hydrogen chloride |
CN102826512B (en) * | 2011-06-16 | 2015-02-18 | 跨特株式会社 | Manufacturing method and apparatus of high-purity hydrogen chloride |
CN102502500A (en) * | 2011-11-07 | 2012-06-20 | 韩扶军 | Device for producing hydrogen chloride by resolving hydrochloric acid |
CN107848799A (en) * | 2015-08-10 | 2018-03-27 | 昭和电工株式会社 | Chlorination method for preparing hydrogen |
CN107848799B (en) * | 2015-08-10 | 2020-07-17 | 昭和电工株式会社 | Method for producing hydrogen chloride |
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US6540973B1 (en) | 2003-04-01 |
JP2001192202A (en) | 2001-07-17 |
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